unique if
Table of Contents
Unique if evaluates all the conditions parallel.
In the following conditions simulator issue a run time error/warning,
- More than one condition is true
- No condition is true or final if doesn’t have corresponding else
Unique if example’s
In the below example,
More than one condition is true.
value of a=10, b=20 and c=40. conditions a<b and a<c are true,
Therefore on execution, simulator issue a run time warning.
“RT Warning: More than one condition match in ‘unique if’ statement.”
module unique_if;
//variables declaration
int a,b,c;
initial begin
//initialization
a=10;
b=20;
c=40;
unique if ( a < b ) $display("\t a is less than b");
else if ( a < c ) $display("\t a is less than c");
else $display("\t a is greater than b and c");
end
endmodule
Simulator Output
a is less than b RT Warning: More than one conditions match in 'unique if' statement.
Unique if example 2
In below example,
No condition is true and final if doesn’t have corresponding else.
value of a=50, b=20 and c=40, conditions a<b and a<c are false,
Therefore on execution, simulator issue a run time warning.
“RT Warning: No condition matches in ‘unique if’ statement.”
module unique_if;
//variables declaration
int a,b,c;
initial begin
//initialization
a=50;
b=20;
c=40;
unique if ( a < b ) $display("\t a is less than b");
else if ( a < c ) $display("\t a is less than c");
end
endmodule
Simulator Output
RT Warning: No condition matches in 'unique if' statement
Unique if example 3
In below example, value of a=50, b=20 and c=40.
conditions a<b and a<c are false, so else part is true, there is no simulator run time warning.
module unique_if;
//variables declaration
int a,b,c;
initial begin
//initialization
a=50;
b=20;
c=40;
priority if ( a < b ) $display("\t a is less than b");
else if ( a < c ) $display("\t a is less than c");
else $display("\t a is greater than b and c");
end
endmodule
Simulator Output
a is greater than b and c